Why global warming causes more warming

If you do a piece of work and get positive feedback from your teacher or boss, then you might work even harder on the next piece of work. This could form a cycle whereby you do well, so you do better the next time, then you do even better the time after that.

Positive feedback loops also exist in nature, but in the case of climate change they are not such a good thing; they accelerate global warming [1].

2) Higher temperatures cause a change in the air, on the ground, or in the ocean, which makes temperatures increase even more [1,3]

Point 2 constantly reinforces itself, leading to a “snowballing” effect [3]. Climate feedback loops involve, for example: melting ice, melting permafrost, and water vapor [4] – we cover each of these in detail in other posts.

Together, climate feedback loops cause the global average temperature to increase much more than if human greenhouse gas emissions acted alone, without causing feedback loops [5]. It’s estimated that doubling the amount of carbon dioxide in the atmosphere would directly cause warming of 1.2°C; but due to feedback loops, the actual temperature change (after a time delay) would be between 2°C and 4.5°C [5]!

How feedback loops will respond to future warming is difficult to predict, and this is one of the main reasons we are so uncertain about how the climate will change in the future [6,4,7,8,9].